A backboard of an existing high-end active matrix organic light emitting diode (AMOLED) product with medium or small size mostly employs a process technology of low temperature poly-silicon (LTPS); however, since fluctuation of LTPS process will lead to drift of the threshold voltage of a thin film transistor (TFT) device, rendering current for driving organic light emitting diode (OLED) device unstable and resulting in a decrease in the display quality of pictures. Pixel compensation circuit as known is a circuit of 6T1C type (a circuit formed by six thin film transistors and one capacitor), and the circuit diagram is shown in FIG. 1, where VDD is a high voltage level signal, VSS is a low voltage level signal, Data is a data signal, Gate is a gate control signal, Reset is an initialization control signal, Vinit is an initialization voltage level signal, Emission (that is, EM) is a signal for controlling light emission of OLED and is provided by the light emission circuit of the OLED panel. However, it is not easy to dispose six thin film transistors and one capacitor in one pixel, and since it needs the TFT devices to be made very small, and thus requirements for performance of the TFT devices are also relatively high, which may cause a pixel pitch to be unable to be further decreased.
As shown in FIG. 2, for the 6T1C circuit as known, devices which needs to be disposed on a horizon direction of two pixels includes two data signal lines (Data v1 and Data v2), twelve TFTs, two capacitors, one gate control signal line Gate, one light emission control signal terminal Emission, one high voltage level signal terminal VDD, one initialization voltage level signal terminal Vinit, and one initialization control signal terminal Reset; in FIG. 2, there are two organic light-emitting diodes, OLED 1 and OLED 2, and each of the cathodes thereof is connected to a low voltage level signal VSS. FIG. 2 is a circuit schematic diagram of two pixels arranged in horizon, and a pixel unit formed in the vertical direction is similar to the pixel unit formed in the horizontal direction, that is, the devices that needs to be disposed in the vertical direction includes one data signal line, twelve TFTs, two capacitors, two gate control signal lines, one light emission control signal terminal Emission, one high voltage level signal terminal VDD and one initialization voltage level signal terminal Vinit.
As described above, as known, there needs to dispose 12 TFTs and two capacitors in two pixels.